Electromagnetic switching assembly

ABSTRACT

An improved electromagnetic switching device having switch means mounted within a housing. The housing has front and rear sections, and first and second side sections interposed between the front and rear sections. The front and rear sections and the first and second side sections each have windows extending therethrough. A movable magnet is mounted in the housing and positioned for reciprocal movement between an energized and a deenergized position. An operating coil for energizing the device is positioned in the housing so that one end of the coil is retained within the window in the front section of the housing and the other end of the coil is retained within the window in the rear section of the housing. The coil has an opening therethrough for receiving a stationary magnet which is in juxtaposition with the movable magnet. One end of the stationary magnet is positioned within the window in the first side section of the housing, and the other end of the stationary magnet is positioned within the window in the second side section of the housing to prevent removal of the coil through the window in the front section. Means is provided for actuating the switch means in response to movement of the movable magnet. Means are also provided for holding the stationary magnet within the respective windows in the first and second side sections of the housing, whereby upon release of the holding means, the stationary magnet is removable from the opening in the coil so as to enable the coil to be removable from the housing through the window in the housing&#39;&#39;s front section.

United States Patent. [191 Hardman i 3,840,830 51 Oct. 8, 1974 [22]Filed:

l ELECTROMAGNETIC SWITCHING ASSEMBLY [75] lnventor: Dorsey LorraineHardman,

Lexington, Ill.

[73] Assignee: General Electric Company, New

York, NY.

Oct. 29, 1973 [21] App]. No.: 410,527

Primary ExaminerHarold Broome Attorney, Agent, or FirmS. A. Young; P. L.Schlamp; R. G. Simkins [57] ABSTRACT An improved electromagneticswitching device having switch means mounted within a housing. Thehousing has front and rear sections, and first'and second side sectionsinterposed between the front and rear sections. The front and rearsections and the first and second side sections each have windowsextending therethrough. A movable magnet is mounted in the housing andpositioned for reciprocal movement between an energized and adeenergized position. An operating coil for energizing the device ispositioned in the housing so that one end of the coil is retained withinthe window in the front section of the housing and the other end of thecoil is retained within the window in the rear section of the housing.The coil has an opening therethrough for receiving a stationary magnetwhich is in juxtaposition with the movable magnet. One end of thestationary magnet is positioned within the window in the first sidesection of the housing, and the other end of the stationary magnet ispositioned within the window in the second side section of the housingto prevent removal of the coil through the window in the front section.Means is provided for actuating the switch means in response tomovementof the movable magnet. Means are also provided for holding thestationary magnet within the respective windows in the first and secondside sections of the housing, whereby upon release of the holding means,the stationary magnet is removable from the opening in the coil so as toenable the coil to be removable from the housing through the window inthe housings front section.

9 Claims, 5 Drawing Figures ELECTROMAGNETIC SWITCHING ASSEMBLYBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to an electromagnetic switching device, and more particularly toan electromagnetic switching device which can have its operating coilremoved without requiring the disassembly of the devices housing.

2. Description of the Prior Art Electromagnetic switching devices, andmore particularly an industrial control relay described in copending US.application Ser. No. 383,685, filed July 30,

1973, inventors Phillip G. Hughes and Dorsey Hardman, entitledIndustrial Control Relay, and assigned to the assignee as the assigneeof the present invention, is provided with switch means mounted within ahousing. Also mounted within the housing is a stationary magnetpositioned within an opening in an operating coil and a movable magnetpositioned for reciprocal movement between an energized and adeenergized position. Means is provided for actuating the switch meansin response to movement of the movable magnet. The housing is comprisedof a plurality of molded sections which are fastened together in abox-like construction.

Quite often, when the, operating coil fails, or when there is a designor system change, replacement of the operating coil becomes necessary.However, such replacement of the operating coil requires unfastening anddisassembly of the housing sections and many of the relay components.Therefore, upon replacement of the operating coil, many components ofthe relay would have to be reassembled and the housing sections wouldhave to be refastened together again. This is not only time consuming,but when the operating coil is replaced under field conditions, variouscomponents of the relay can be misplaced so as to prevent it from beingplaced back into operation.

OBJECTS OF THE INVENTION It is therefore an objectof this invention toprovide an improved electromagnetic switching device which is capable ofhaving its operating coil replaced without requiring disassembly of thedevices housing and various other components.

It is another object of this invention to provide for quick and easyreplacement of the operating coil of the relay without running the riskof having various components of the relay misplaced in the interim.

Other objects of the invention will be pointed in and understood fromthe following.

SUMMARY OF THE INVENTION In accordance with a broad aspect of theinvention there is provided an electromagnetic switching device havingswitch means mounted within a housing. The housing has front and rearsections, and first and second side sections interposed between thefront and rear sections. The front and rear sections and the first andsecond side sections each have windows extending therethrough. A movablemagnet is mounted in the housing for reciprocal movement between anenergized and a deenergized position. An operating coil for energizingthe device is positioned in the housing. The coil has an openingtherethrough, and one end of the coil is retained within the window ofthe from section of the housing. A stationary magnet is positionedwithin the opening in the coil and in juxtaposition with the movablemagnet. Means for actuating the switch means in response to movement ofthe movable magnet is provided. Also provided is means for holding oneend of the stationary magnet within the window in the first side sectionof the housing to prevent removal of the coil through the window in thefront section, whereby upon release of the holding means, the stationarymagnet is removed from the opening in the coil to enable the coil to beremoved from the housing through the window in the front section. Theholding means is comprised of a spring member positioned within a pocketin the housing and pressing against a bottom portion and a substantiallyvertical side wall portion bounding a channel formed within the topsurface of the stationary magnet. Also provided is a flat spring whichbears against the top of the operating coil so as to prevent anyunnecessary movement of the coil'during operation of the relay.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of theassembled electromagnetic device;

FIG. 2 is an exploded perspective view of elements of the device shownin FIG. 1 showing the removal of the operating coil through the windowin the front section of the housing;

relay;

FIG. 4 is a cross sectional view of the lower half of the relay takenalong lines 44 in FIG. 3; and

FIG. 5 is a cross sectional view of the lower half of the relay takenalong lines 55 in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention will now beexplained with reference to FIGS. l-5. As shown in FIG. 1, the housingfor a relay 10 is comprised of a metal base plate 12, a pair of moldedplastic lower half sections 14a and 14b, a molded plastic upper housingsection 16 and a molded plastic housing cover 18. Lower molded halfsections 14a and 14b are fastened to base plate 12 using respectivethreaded fasteners 19a and 19b. Upper housing section 16 is fastened tolower molded half sections and 14b using standard fastening techniques,such as a threaded fastener 20. Similarly, housing cover 18 is fastenedto upper housing section 16 using threaded fasteners 21a and 21b.

As more specifically shown in FIGS. 2 and 4, relay 10 is furthercomprised of a U-shaped movable magnet 22 mounted within the housing forreciprocal movement between an energized and a deenergized position. Anoperating coil 24, having an opening 26 therethrough and first andsecond current carrying terminals 280 and 28b extending therefrom, issuitably mounted within the housing. A one piece rigid member 30 hasportions 32a and 32b fixed to respective pole faces 34a and 34b ofmagnet 22. Member 30 has actuating portions 36a and 36b extendingupwardly from the pole faces of movable magnet 22. Switch means, in theform of a plurality of switch modules, is provided, although in FIG. 2only a single switch module 38 is shown. Means for actuating the switchmeans is provided by a one piece yoke member 40 having raised portions42 extending from a top surface thereof to form pockets,.'wherein FIG. 3is a side elevation view of the lower half of the each pocket receivesone end 44 of a plunger 46 that extends through the bottom of anenclosure 48 for switch module 38. The other end 50 of plunger 46engages spring loaded means mounted within housing cover 18. A shaft 52,shown in FIG. 1, extends from the top surface of yoke 40 and through thetop surface of housing cover 18. A stationary magnet 54 is positionedwithin opening 26 of coil 24, and is placed juxtaposition with the polefaces of movable magnet 22. A more detailed description of the relayscomponents such as movable magnet 22, rigid member 30, operating coil24, switch module 38, yoke 40, stationary magnet 54, etc., their methodof assembly and operation is found in copending US. application Ser. No.383,685, filed July 30,1973, inventors Philip G. Hughes and DorseyHardman, entitled Industrial Control Relay," and assigned to the sameassignee as the assignee of the present invention. Only those details ofthe relay components and housing necessary for the understanding of thisinvention will now be further explained.

A front section 56 of the relay housing has a window 58 therein which isdimensioned to allow coil 24 to pass therethrough. A rear section 60 ofthe housing also has a window 62 therein which is of the sameapproximate dimension as the dimension of window 58. A one piece bowedspring member 64, having opposite ends 66a and 66b located withinrespective pockets 68a and 68b formed by the molded interior of thehousing, is shown in FIG. to bear against the top surface of coil 24 sothat those portions of the bottom surface of the coil which are adjacentopposite ends thereof bear against respective lower ledges 70a and 70bof respective windows 58 and 62. Bowed spring 64 applies sufficientforce to coil 24 to prevent the coil from moving unnecessarily duringoperation of the relay.

As shown in FIG. 4, a first side section 72 of the housing has a window74 therein dimensioned to allow stationary magnet 54 to passtherethrough. Similarly, a second side section 76 of the housing has awindow 78 therein which also is dimensioned to allow stationary magnet54 to pass therethrough. As shown in FIG. 4, when the relay isassembled, stationary magnet 54 is positioned within opening 26 in coil24, and those portions of the bottom surface of magnet 54 adjacent itsrespective opposite ends respectively rest on a ledge 80 of window 74and a ledge 82 of window 78. A first channel 84 is formed within a topsurface and adjacent an end 85 of stationary magnet 54 that ispositioned within window 74 of first side section 72 of the housing.Similarly a second channel 86 is formed within the top surface andadjacent the other end 87 of stationary magnet 54 that is positionedwithin window 78 of second side section 76 of the housing. Channel 84 isbounded by a bottom portion 88, a substantially vertical side wallportion 90 extending upwardly from one edge of bottom portion 88, and anupwardly extending sloping side wall portion 92 extending upwardly fromthe opposite edge of bottom portion 88 and toward the second sidesection of the housing. Vertical side wall portion 90 is positionedcloser to window 74 in first side section 72 of the housing than isupwardly extending sloping side wall portion 92. Second channel 86 islikewise bounded by a bottom portion 94, a substantially vertical sidewall portion 96 extending upwardly from one edge of bottom portion 94,and a sloping side wall portion 98 extending upwardly from the oppositeedge of bottom portion 94 and toward first side section 72. Verticalside wall portion 96 is positioned closer to second side section 76 thanis sloping side wall portion 86.

Means for holding that portion of the stationary magnet, which isadjacent first side section 72, within window 74 is provided by aresilient spring clip 100 shown in FIG. 4. Similarly means for holdingthat portion of the stationary magnet, which is adjacent second side 76,within window 78 is provided by a second spring clip 102. Since secondspring clip 102 is identical in configuration, operation andinstallation to first spring clip 100, only details relating to thestructure of spring clip 102, its installation and operation will beexplained. As shown in FIG. 3, spring clip 102, which is made of asuitably structured metal or plastic, is comprised of first and secondbase sections 104 and 106, respective curled end sections 108 and 110,and a medial looped section 112 extending between base sections 104 and106. Curled end sections 108 and 110 provide spring clip 102 with therequired degree of resiliency necessary for its successful operation,and they are suitably located within appropriate slots formed in theinterior of respective lower molded half sections 14a and 14b of thehousing (not shown). As shown in FIGS. 3 and 4, those portions of basesections 104 and 106 adjacent looped section 112 of spring clip 102 arepositioned within second channel 86 and abut bottom portion 94 andvertical side wall portion 96 so that stationary magnet 54 is firmlyheld within window 78 and cannot move toward first side section 72.Looped section 112 extends past the upper most edge of vertical sidewall section 96 and over the top surface of stationary magnet 54. Theanalogous components of spring clip 100 are also positioned withinchannel 84 to hold.

stationary magnet 54 firmly within window 74 so that the stationarymagnet cannot move toward second side section 76.

In operation, a suitable tool such as a screwdriver 114 has its endpositioned between looped section 112 of spring clip 102 and the topsurface of stationary magnet 54. The tool is then moved downward asindicated in FIGS. 1 and 4 by an operator until those portions of basesections 104 and 106 of spring clip 102 are forced upward and out ofengagement with vertical side wall portion 96 bounding second channel86. Now the operator places his fingers within window 78 and pushesagainst the side of stationary magnet 54 so as to move stationary magnet54 out from window 78, through opening 26 in coil 24 and out of thehousing through window 74. Those sections of spring clip 100, which areinitially positioned within bottom portion 88 and adjacent vertical sidewall portion bounding channel 84, glide up over sloping side wallportion 92 and onto thetop surface of stationary magnet 54. Stationarymagnet 54 continues its movement out of the housing through window 74until it is no longer positioned within opening 26 of coil 24. Finallythe above mentioned sections of spring clip slide down sloping side wallsection 98 and into second channel 86 in such a manner as to abutvertical side wall portion 96, and thereby prevent the complete removalof the stationary magnet from the housing. Now, by applying sufficientpressure to coil 24 to overcome the holding force of flat spring member64, coil 24 is easily removed from the housing through window 58 infront section 56. Coil 24 is then either repaired, remodeled or replacedwith another suitable coil. The new or re paired coil is thenrepositioned within the housing through window 58 in front section 56until it again is in its proper assembled position. Then stationarymagnet 54 is pushedback to its assembled position within the housingfrom window 74, through opening 26 in coil24 and into window 78 untilspring clip 100 engages substantially vertical side wall portion 90bounding channel 84 and spring clip 102 engages substantially verticalside wall portion 96 bounding channel 86. Alternatively, the screwdrivercan be used to force spring clip '100 out of engagement with verticalside wall portion 90 so that the stationary magnet can be pushed out ofthe housing through window 76 to enable removal of coil 24 from thehousing.

It is thus seen that the just described configuration provides for easyand fast removal and a replacement of theoperating coil withoutrequiring the undesired disassembly of the relay housing and most of itscomponents. I

It should be noted that in another form of the invention rear window 62in rear section 60 of the housing can be eliminated, and the adjacentend of coil 24 can rest on an inwardly extending molded ledge which canbe formed in the interior of rear section 60. Similarly, both window 78in second side section 76 of the housing and spring clip 102 can beeliminated, and the adjacent end 87 of stationary magnet 54 can restupon an inwardly extending ledge which can be formed in the interior ofsecond side section 76. Under these circumstances, once the means forholding a stationary magnet within window 74 in first side section 72 ofthe housing is released, stationary magnet 54 would have to be pulledrather than pushed through window 74 until it is clear of opening 26 incoil 24. Under these circumstances it may be necessary to provide means,such as a hook, attached to end 85 of the stationary magnet tofacilitate the pulling of stationary magnet 54 through window 74.

Although the invention has been described with reference to a specificembodiment thereof, numerous modifications are possible withoutdeparting from the invention and it is desirable to cover allmodifications of the invention falling within the spirit and scope ofthis invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. An electromagnetic switching device comprising:

a. a housing having front and rear sections and first and second sidesections interposed between said front and rear sections, said frontsection and said first side section having windows extendingtherethrough;

b. a movable magnet mounted in said housing for reciprocalmovementbetween an energized and a deenergized position;

c. an operating coil for energizing said device positioned in saidhousing, said coil having an opening therethrough, one end of said coilbeing retained within the window in thefront section of said housing;

d. a stationary magnet positioned within the opening in said coil and injuxtaposition with said movable magnet;

e. switch means;

' f. means for actuating said switch means in response to movement ofsaid movable magnet; and

g. a first spring clip having a first and a second part positionedwithin said housing, said first part of said first spring clip being inlocking engagement with said stationary magnet for holding that portionof said stationary magnet adjacent one end thereof within the window insaid first side section of said housing to prevent removal of said coilthrough the window in said front section, said second part of said firstspring clip extending from said first part and over the top surface ofsaid stationary magnet, whereby a tool is receivable between the topsurface of said stationary magnet and said second part of said firstspring clip, and upon proper movement of the tool, said first part ofsaid first spring clip is moved out of locking engagement with saidstationary magnet, thereby rendering said stationary magnet removablefrom the opening in said coil to enable said coil to be removed fromsaid housing through the window in said front section.

2. An electromagnetic switching device according to claim 1, whereinsaid rear section and said second side section have windows extendingtherethrough, and the windows in said front and rear sections and saidfirst and second side sections are each partially bounded by a bottomledge.

3. An electromagnetic switching device according to claim 2, whereinsaid coil has a top surface and a bottom surface, further comprising abowed spring positioned within said housing and bearing against the topsurface of said coil to press those portions of the bottom surface ofsaid coil adjacent said one end and another end thereof against thebottom ledge bounding the windows in said respective front and rearsections.

4. An electromagnetic switching device according to claim 2, furthercomprising a second spring clip having a first and a secondpartpositioned within said housing both before and after said coil isremoved from said housing, said first part of said second spring clipbeing in locking engagement with said stationary magnet for holding thatportion of said stationary magnet adjacent another end thereof withinthe window in said second side section, said second part of said secondspring clip extending from said first part of said second spring clipand over the top surface of said stationary magnet, whereby a tool isreceivable between the top surface of said stationary magnet and saidsecond part of said second spring clip, and upon proper movement of thetool, said first part of said second springclip is moved out of lockingengagement with said stationary magnet, thereby rendering saidstationary magnet removable from the window in said second side section,through the opening in said coil, and then out of said housing throughthe window in said first side section.

5. An electromagnetic switching device according to claim 4, whereinsaid stationary magnet has a first and a second channel formed within atop surface thereof, said first channel being adjacent said one end ofsaid stationary magnet, and said second channel being adjacent saidother end of said stationary magnet.

6. An electromagnetic switching device according to claim 5, whereineach of said first and second channels is bounded by a bottom portion, asubstantially vertical side wall portion extending from one edge of saidbottom portion, and a sloping side wall portion extending from anopposite edgeof said bottom portion and away from said vertical sidewall portion.

7. An electromagnetic switching device according to claim 6, whereinsaid one end of said stationary magnet is closer to said substantiallyvertical side wall portion bounding said first channel than to saidsloping side wall portion bounding said first channel, and said otherend of said stationary magnet is closer to said substantially verticalside wall portion bounding said second channel than to said sloping sidewall portion bounding said second channel.

8. An electromagnetic switching device according to claim 7, whereinsaid first part of said second spring clip engages said bottom portionand said substantially vertical side wall portion bounding said secondchannel to prevent said stationary magnet from moving in a directiontoward the window in said first side section of said housing, wherebyupon proper movement of the tool, said first part of said second clip islifted over and out of engagement with said substantially vertical sidewall portion bounding said second channel, thereby re- 8 leasing saidstationary magnet for movement in the direction toward the window insaid first side section of said housing.

9. An electromagnetic switching device according to claim 8, whereinsaid first part of said first spring clip engages said bottom portionand said substantially vertical side wall portion bounding said firstchannel to prevent said stationary magnet from moving in a directiontoward the window in said second side section of said housing, wherebyafter said stationary magnet has been released and moved in a directiontoward the window in said first side section of said housing, said firstspring clip engages said bottom portion and said substantially verticalside wall portion bounding said second channel to prevent the removal ofsaid stationary magnet from said housing while said coil is beingremoved from said housing.

1. An electromagnetic switching device comprising: a. a housing havingfront and rear sections and first and second side sections interposedbetween said front and rear sections, said front section and said firstside section having windows extending therethrough; b. a movable magnetmounted in said housing for reciprocal movement between an energized anda deenergized position; c. an operating coil for energizing said devicepositioned in said housing, said coil having an opening therethrough,one end of said coil being retained within the window in the frontsection of said housing; d. a stationary magnet positioned within theopening in said coil and in juxtaposition with said movable magnet; e.switch means; f. means for actuating said switch means in response tomovement of said movable magnet; and g. a first spring clip having afirst and a second part positioned within said housing, said first partof said first spring clip being in locking engagement with saidstationary magnet for holding that portion of said stationary magnetadjacent one end thereof within the window in said first side section ofsaid housing to prevent removal of said coil through the window in saidfront section, said second part of said first spring clip extending fromsaid first part and over the top surface of said stationary magnet,whereby a tool is receivable between the top surface of said stationarymagnet and said second part of said first spring clip, and upon propermovement of the tool, said first part of said first spring clip is movedout of locking engagement with said stationary magnet, thereby renderingsaid stationary magnet removable from the opening in said coil to enablesaid coil to be removed from said housing through the window in saidfront section.
 2. An electromagnetic switching device according to claim1, wherein said rear section and said second side section have windowsextending therethrough, and the windows in said front and rear sectionsand said first and second side sections are each partially bounded by abottom ledge.
 3. An electromagnetic switching device according to claim2, wherein said coil has a top surface and a bottom surface, furthercomprising a bowed spring positioned within said housing and bearingagainst the top surface of said coil to press those portions of thebottom surface of said coil adjacent said one end and another endthereof against the bottom ledge bounding the windows in said respectivefront and rear sections.
 4. An electromagnetic switching deviceaccording to claim 2, further comprising a second spring clip having afirst and a second part positioned within said housing both before andafter said coil is removed from said housing, said first part of saidsecond spring clip being in locking engagement with said stationarymagnet for holding that portion of said stationary magnet adjacentanother end thereof within the window in said second side section, saidsecond part of said second spring clip extending from said first part ofsaid second spring clip and over the top surface of said stationarymagnet, whereby a tool is receivable between the top surface of saidstationary magnet and said second part of said second spring clip, andupon proper movement of the tool, said first part of said second springclip is moved out of locking engagement with said stationary magnet,thereby rendering said stationary magnet removable from the window insaid second side section, through the opening in said coil, and then outof said housing through the window in said first side section.
 5. Anelectromagnetic switching device according to claim 4, wherein saidstationary magnet has a first and a second channel formed within a topsurface thereof, said first channel being adjacent said one end of saidstationary magnet, and said second channel being adjacent said other endof said stationary magnet.
 6. An electromagnetic switching deviceaccording to claim 5, wherein each of said first and second channels isbounded by a bottom portion, a substantially vertical side wall portionextending from one edge of said bottom portion, and a sloping side wallportion extending from an opposite edge of said bottom portion and awayfrom said vertical side wall portion.
 7. An electromagnetic switchingdevice according to claim 6, wherein said one end of said stationarymagnet is closer to said substantially vertical side wall portionbounding said first channel than to said sloping side wall portionbounding said first channel, and said other end of said stationarymagnet is closer to said substantially vertical side wall portionbounding said second channel than to said sloping side wall portionbounding said second channel.
 8. An electromagnetic switching deviceaccording to claim 7, wherein said first part of said second spring clipengages said bottom portion and said substantially vertical side wallportion bounding said second channel to prevent said stationary magnetfrom moving in a direction toward the window in said first side sectionof said housing, whereby upon proper movement of the tool, said firstpart of said second clip is lifted over and out of engagement with saidsubstantially vertical side wall portion bounding said second channel,thereby releasing said stationary magnet for movement in the directiontoward the window in said first side section of said housing.
 9. Anelectromagnetic switching device according to claim 8, wherein saidfirst part of said first spring clip engages said bottom portion andsaid substantially vertical side wall portion bounding said firstchannel to prevent said stationary magnet from moving in a directiontoward the window in said second side section of said housing, wherebyafter said stationary magnet has been released and moved in a directiontoward the window in said first side section of said housing, said firstspring clip engages said bottom portion and said substantially verticalside wall portion bounding said second channel to Prevent the removal ofsaid stationary magnet from said housing while said coil is beingremoved from said housing.